Semiconductor device and method for manufacturing the same

Abstract

A semiconductor device and a method for manufacturing the same, in which a leak current generated in a pn junction formed between a silicon substrate and an epitaxial layer can be reduced. A silicon oxide film is formed on a silicon substrate having a (100) crystal plane. The silicon oxide film is patterned to form an opened portion and an inclined surface on a pattern edge of the silicon oxide film. The inclined surface forms an angle of 54.74±5° with the silicon substrate. An epitaxial layer is formed in the opened portion by selective epitaxial growth.

We claim: 
     
       1. A semiconductor device comprising: an insulation film formed on a first conductive-type semiconductor substrate having a (100) crystal plane, the insulation film having a pattern edge surface forming an interior angle of 54.74±5° with the first conductive-type semiconductor; and   a second conductive-type semiconductor layer formed by epitaxial growth method, the second conductive-type semiconductor layer being formed on the first conductive-type semiconductor substrate in contact with the insulation film.   
     
     
       2. The semiconductor device according to claim 1, wherein the second conductive-type semiconductor layer comprises a conductive-type layer in <100> direction and a conductive-type layer in <111> direction. 
     
     
       3. A semiconductor device comprising: an insulation film formed on a first conductive-type semiconductor substrate having a (100) crystal plane, the insulation film having two pattern edge surfaces forming interior angles of 54.74±5° and 125.26±5° with the first conductive-type semiconductor; and   a second conductive-type semiconductor layer formed by epitaxial growth method, the second conductive-type semiconductor layer being formed on the first conductive-type semiconductor substrate in contact with the insulation film.   
     
     
       4. The semiconductor device according to claim 3, wherein the second conductive-type semiconductor layer comprises a conductive-type layer in <100> direction and a conductive-type layer in <111> direction. 
     
     
       5. A semiconductor device comprising: an insulation film formed on a first conductive-type semiconductor substrate having a (111) crystal plane, the insulation film having a pattern edge surface forming an interior angle of 38.94±5° with the first conductive-type semiconductor; and   a second conductive-type semiconductor layer formed by epitaxial growth method, the second conductive-type semiconductor layer being formed on the first conductive-type semiconductor substrate in contact with the insulation film.   
     
     
       6. The semiconductor device according to claim 5, wherein the second conductive-type semiconductor layer comprises a conductive-type layer in <111> direction and a conductive-type layer in <111> direction. 
     
     
       7. A semiconductor device comprising: an insulation film formed on a first conductive-type semiconductor substrate having a (111) crystal plane, the insulation film having two pattern edge surfaces forming interior angles of 38.94±5° and 109.47±5° with the first conductive-type semiconductor; and   a second conductive-type semiconductor layer formed by epitaxial growth method, the second conductive-type semiconductor layer being formed on the first conductive-type semiconductor substrate in contact with the insulation film.   
     
     
       8. The semiconductor device according to claim 7, wherein the second conductive-type semiconductor layer comprises a conductive-type layer in <111> direction and a conductive-type layer in <111> direction. 
     
     
       9. A method for manufacturing a semiconductor device comprising the steps of: forming an insulation film on a conductive-type semiconductor substrate having a (100) crystal plane;   patterning the insulation film to form an opened portion and an inclined surface on a pattern edge of the insulation film, the inclined surface forming an angle of 54.74±5° with the conductive-type semiconductor substrate; and   forming an epitaxial layer in the opened portion by selective epitaxial growth.   
     
     
       10. The method for manufacturing a semiconductor device according to claim 9, wherein the opened portion is formed by patterning the insulation film parallel and perpendicular to <110> direction. 
     
     
       11. A method for manufacturing a semiconductor device comprising the steps of: forming an insulation film on a conductive-type semiconductor substrate having a (111) crystal plane;   patterning the insulation film to form an opened portion and an inclined surface on a pattern edge of the insulation film, the inclined surface forming an angle of 38.94±5° with the conductive-type semiconductor substrate; and   forming an epitaxial layer in the opened portion by selective epitaxial growth.   
     
     
       12. The method for manufacturing a semiconductor device according to claim 11, wherein the opened portion is formed by patterning the insulation film parallel and perpendicular to <2-11> direction.